Process for the saccharification of celluloses

Abstract

A process for the saccharification of celluloses is provided. More particularly, a solution obtained after the degradative saccharification of cellulosic materials with cellulases is separated into a liquid portion containing saccharides and a solid matter. Cellulases are recovered from said liquid portion containing saccharides, while said solid matter is treated with an aqueous pH-buffered solution, or an aqueous solution, alcoholic aqueous solution or aqueous pH-buffered solution of polysaccharides or oligosaccharides, or aqueous or aqueous pH-buffered solution of alcohols to recover the cellulases in the solid matter. With the use of this solid matter, newly added cellulosic materials are degradatively saccharified in an aqueous solution or the above-mentioned solutions.

What is claimed is: 
     
       1. A process for the saccharification of celluloses, comprising degradatively decomposing a cellulosic material by cellulases in the absence of an alcohol to obtain a liquid portion containing saccharides and a solid matter containing cellulases; separating said liquid portion from said solid matter; and degradatively saccharifying additional cellulosic material with the use of said solid matter in an aqueous solution, an aqueous pH-buffered solution or an aqueous pH-buffered solution of polysaccharides or oligosaccharides. 
     
     
       2. A process for the saccharification of celluloses as set forth in claim 1, wherein said polysaccharide is glucomannan, xylan, galactan, galactoglucomannan, or a mixture thereof. 
     
     
       3. A process for the saccharification of celluloses as set forth in claim 1, wherein said oligosaccharide is cellobiose, cellotriose, cellotetraose, cellopentaose, cellohexaose, glucose-containing mannooligosaccharide, or a mixture thereof. 
     
     
       4. A process for the saccharification of celluloses as set forth in claim 1, wherein the concentration of said polysaccharides or oligosaccharides in said aqueous solution, or aqueous pH-buffered solution is within the range of 0.5 to 5 percent by weight. 
     
     
       5. A process for the saccharification of celluloses as set forth in claim 1, wherein the pH value of said aqueous pH-buffered solutions is within the range of 3.0 to 8.0. 
     
     
       6. A process for the saccharification of celluloses as set forth in claim 1, wherein said newly added cellulosic materials are degradatively saccharified by said solid matter at a temperature ranging from room temperature to 55° C.